1. Field of the Invention
The present disclosure relates to an optical read/write apparatus and read apparatus that reads and writes data from/on an optical storage medium such as an optical tape, an optical disc or an optical card using multiple optical pickups in parallel.
2. Description of the Related Art
Recently, the size of digital data to process has been rising steeply year by year as the resolutions of video data and still picture data have been tremendously increased and as increasing numbers of paper media have been converted into electronic ones. Meanwhile, so-called “crowd computing” technologies that allow people to use various kinds of applications and services via servers and storage systems on some network have become more and more popular nowadays. According to such crowd computing technologies, as a huge number of users save various kinds of data on that storage system on the network, the amount of data accumulated there should keep on skyrocketing from now on.
In the meantime, as regulations have been established one after another with regard to the duty of preserving such a huge amount of data saved, it should also be increasingly important to devise a method for saving that enormous amount of data as securely and as reliably as possible.
In order to write data of such a huge size optically on a storage medium, an apparatus that performs read/write operations in parallel by arranging multiple sets of light-emitting and light-receiving elements with respect to an optical storage medium has been proposed as disclosed in Japanese Laid-Open Patent Publication No. 3-201222 (which will be referred to herein as “Patent Document No. 1” for convenience sake).
FIG. 20 is a schematic representation illustrating a part of a simplified version of the apparatus disclosed in Patent Document No. 1. As shown in FIG. 20, multiple sets of light-emitting elements 802 and light-receiving elements 803 are arranged to face the same side of an optical recording tape 801. In this example, six sets of light-emitting elements 802 and light-receiving elements 803 are arranged and read/write operations can be performed in parallel by using them simultaneously.
Although Patent Document No. 1 does not mention the operation of seeing if data has been written as intended on an optical storage medium (which will be referred to herein as a “verify operation”), an apparatus that is designed to write such an enormous amount of data on an optical storage medium should do that verify operation to increase the reliability of storage. Thus, to meet such demand, a so-called “DRAW (direct read after write)” technology for performing a write operation and a read operation for verification purposes simultaneously has been proposed. A known read/write apparatus that adopts the DRAW technology is disclosed in Japanese Laid-Open Patent Publication No. 6-162532 (which will be referred to herein as “Patent Document No. 2” for convenience sake).
Patent Document No. 1 does not disclose the verify operation of seeing if data has been written as intended by getting the data that has been written by the light-emitting elements 802 on the optical recording tape 801 read by the light-receiving elements 803.
On the other hand, Patent Document No. 2 does disclose a read/write apparatus that performs a verify operation but fails to disclose a configuration for detecting any data that has not been written successfully on an optical storage medium and writing that data all over again elsewhere in a short time.
Thus, an embodiment of the present invention provides an optical read/write apparatus that sees if there is any data that has been written unsuccessfully on the storage area of a given optical storage medium or if there is anything wrong with the storage medium and that can quickly write the data in question elsewhere if the answer is YES.